Federal prosecutors are asking a judge to reduce the eight-year prison sentence for a convicted former New Orleans police officer who fired his gun on the Danziger Bridge and later took part in a massive cover-up.

Ellis Lucia / The Times-Picayune archiveOfficer Michael Hunter, in black jacket, was surrounded by supportive New Orleans police as he turned himself in in January 2007 to face state criminal charges.

Prosecutors filed a motion Monday requesting that U.S. District Court Judge Sarah Vance trim former officer Michael Hunter's sentence to five years in light of his cooperation and testimony in the high-stakes civil rights trial.

Hunter pleaded guilty earlier last year to misprision of a felony -- or failing to report a federal crime -- and conspiracy to obstruct justice. Vance sentenced him to eight years in prison, the maximum sentence, and he is scheduled to report to a federal prison on Friday.

In arguing for the reduction, prosecutors note that Hunter "provided an unflinchingly honest account of the incident on the bridge, even admitting personal wrongdoing about which federal investigators previously had no knowledge."

Hunter admitted that he fired the initial shots, not his colleague, Sgt. Kenneth Bowen. Prosecutors wrote that Hunter "offered compelling and brutally honest testimony" and that his "cooperation was unfaltering throughout the prosecution of this case."

Hunter drove the speeding box truck of officers to the base of the Danziger Bridge on Sept. 4, 2005. Hunter fired his gun outside the window before the vehicle came to a stop. Police colleagues soon piled out of the truck and opened fire on six unarmed civilians, killing two.

Hunter testified at trial that he assumed at the time that the people on the bridge had guns and that they had fired upon officers because his colleagues heard a distress call that said so.

But the officers never saw any guns and never issued any commands to the civilians, Hunter said. Hunter's testimony, from his front-seat vantage point, provided some of the most detailed eyewitness testimony about the police shooting. He also described how a group of officers concocted a vast cover-up that persisted for several years.

Five current or former officers were convicted last month following a lengthy trial. Five others previously pleaded guilty and agreed to cooperate with federal investigators.Vance has yet to rule on the government's request for a reduction in Hunter's sentence.

Prosecutors asked earlier this month for a reduction in former officer Jeffrey Lehrmann's three-year sentence, though a different federal judge rebuffed the request.